The Green Bay Packers and Oakland Raiders played their preseason game Thursday night in Winnipeg on a shortened field because of turf problems related to moving the goal posts from a Canadian Football League setup to an NFL configuration.

In the CFL, goal posts are at the front of the end zone instead of at the back of it, as they are in the NFL. When officials examined the turf before the game Thursday at the spots from which the goal posts had been removed, they determined that the field conditions were a safety issue for players.

“The field met the mandatory practices for the maintenance of surfaces for NFL games based on inspection [Wednesday],” the league said in a written statement. “Concerns arose [Thursday] surrounding the area where the Blue Bombers’ goal posts were previously located.”

The 10-yard lines were treated as the goal lines for the game. Kickoffs were eliminated, with the football simply being placed at a designated spot to start the next drive instead.

Both teams withheld starters from the game. That included Packers quarterback Aaron Rodgers, who had been scheduled to make his preseason debut in the offense of Coach Matt LaFleur. Rodgers sat out last week’s game at Baltimore because of tightness in his back. If he also is held out of the preseason finale, his first game action playing for LaFleur will be in the regular season.

The NFL has had some issues with field conditions at non-NFL stadiums in recent years. The Rams-Chiefs game last season that was scheduled to be played in Mexico City instead was played in Los Angeles because of issues with the field. The Hall of Fame Game was canceled in 2016 because of concerns about the condition of the field in Canton, Ohio.

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